Discussion
If I remember rightly, the MG metro cam wasn't half bad as it is. Perhaps someone here can confirm this? Somewhat similar to a kent 266? That being the case then im not sure I would uprate it further without some other engine modifications first (that is if the cam is in good condition still).
What else have you got planned for the engine? Like head/valves, rockers? rebore to larger capacity? If the capacity is to remain largely unchanged, then I think I wouldnt put anything more ambitious then a kent 276 in there.
I've been somewhat out of the Mini loop of late though, so perhaps the Kent cams have been bettered by now. I read a lot of good press about Swiftunes cams, so those are likely well worth a look also.
P,
What else have you got planned for the engine? Like head/valves, rockers? rebore to larger capacity? If the capacity is to remain largely unchanged, then I think I wouldnt put anything more ambitious then a kent 276 in there.
I've been somewhat out of the Mini loop of late though, so perhaps the Kent cams have been bettered by now. I read a lot of good press about Swiftunes cams, so those are likely well worth a look also.
P,
your main problem will be emmissions, so stay away from anything 286 upwards, particually if you are using a HIF44, which, when worn are very intolarant (emmissons wise) of lumpy cams, unless its a early car.
if its just a mild 1275 id stick a SW5 or a minispares EVO cam in as they are very good torquey things.
be careful of cheap cams as a lot of people are having problems with cams made abroad to a price rather than a quality, ive heard so real horror stories from people about cams with lobe centres all over the place etc.
if its just a mild 1275 id stick a SW5 or a minispares EVO cam in as they are very good torquey things.
be careful of cheap cams as a lot of people are having problems with cams made abroad to a price rather than a quality, ive heard so real horror stories from people about cams with lobe centres all over the place etc.
If you look at the cam proile data, a Kent 266 is very close to an MG Metro cam an, usually, a lot cheaper. In fact the 266 is a cam I really do like. You might just get away with a 276 emissions-wise and that is also a good cam, but you might need to lower the diff ratio a bit. I don't have any experience with the SW range and so I tend to stick with what I know.
guru is quite right about the 286, it's lumpy for road use, needs a light flywheel and low gearing and will cause MoT problems with emissions. It also need a high compresasion, over 10.5:1, to work at its best.
My advice also is to fit a duplex chain kit and to time in the cam with offset keys to about 2 degrees advanced from manufacturer's recommended to allow for chain stretch. Remember, the chan stretches most in the first 1000 miles and after that the timing is virtually spot-on for a long time.
guru is quite right about the 286, it's lumpy for road use, needs a light flywheel and low gearing and will cause MoT problems with emissions. It also need a high compresasion, over 10.5:1, to work at its best.
My advice also is to fit a duplex chain kit and to time in the cam with offset keys to about 2 degrees advanced from manufacturer's recommended to allow for chain stretch. Remember, the chan stretches most in the first 1000 miles and after that the timing is virtually spot-on for a long time.
Short duration cams (MG metro / Kent 266/276 / SW5) + 1.5 ratio rockers on 1275cc+ give best road manners. This set-up gives good flat torque curves, increased rpm potential (5.5K rpm + no probs) decent emissions, and importantly everyday drivability. My 1275cc Mini with standard cam 
+ 1.5 ratio Roller tip rockers, well prepped Rob Walker head with increased CR, HIF44 and LCB/RC40 gave 64bhp at the wheels and 32mpg. Even when pulled off the road earlier this year with 110K on the clock, continued to sale through MOT's.
Long duration Cams are just a pain in the a*se in modern traffic conditions, and you'll pay dearly at the pumps. All IMHO.
+ 1.5 ratio Roller tip rockers, well prepped Rob Walker head with increased CR, HIF44 and LCB/RC40 gave 64bhp at the wheels and 32mpg. Even when pulled off the road earlier this year with 110K on the clock, continued to sale through MOT's.Long duration Cams are just a pain in the a*se in modern traffic conditions, and you'll pay dearly at the pumps. All IMHO.
FWDRacer said:
Short duration cams (MG metro / Kent 266/276 / SW5) + 1.5 ratio rockers on 1275cc+ give best road manners. This set-up gives good flat torque curves, increased rpm potential (5.5K rpm + no probs) decent emissions, and importantly everyday drivability. My 1275cc Mini with standard cam + 1.5 ratio Roller tip rockers, well prepped Rob Walker head with increased CR, HIF44 and LCB/RC40 gave 64bhp at the wheels and 32mpg. Even when pulled off the road earlier this year with 110K on the clock, continued to sale through MOT's.
Long duration Cams are just a pain in the a*se in modern traffic conditions, and you'll pay dearly at the pumps. All IMHO.
A lot of sense there, if I may say so. + 1.5 ratio Roller tip rockers, well prepped Rob Walker head with increased CR, HIF44 and LCB/RC40 gave 64bhp at the wheels and 32mpg. Even when pulled off the road earlier this year with 110K on the clock, continued to sale through MOT's.Long duration Cams are just a pain in the a*se in modern traffic conditions, and you'll pay dearly at the pumps. All IMHO.
The hotter the cam the lower diff ratio is needed to avoid having to slip the clutch a lot in traffic. With a 296/649 type set-up, if you run a diff to give reasonable cruise on a main road, you'll be slipping the clutch so much you'll end up changing the centre plate every couple of months.
A really nice cam is the old Cooper 'S' one from the 60's, the 510. I used it recently in a 998 bored out to 1061 with Hastings flat-top pistons, with a flowed 295 head with slightly larger inlet valves, an original Cooper 3-into-1 exhaust manifold, an HS4 on a flowed Howley alloy inlet with a No.6 needle and an RC40 small-bore single box exhaust. The CR is 10.3:1. The only thing I didn't do, but should have, was to fit an Aldon 'Yellow' dizzy. However, it goes really well, although it's not been on the rollers yet. That'll happen in the Spring. Incidentally, the diff is a 3.1 with 12" wheels. I guess it does about 35+ mpg. It's a lovely engine and, I feel, a bit more powerful than the average late 1275 unit.
This is a really good compromise. Make sure the head work makes use of the increase in lift and better chamber filling (Get a decent job by a renowned Mini tuner - let us know where you are and the PH collective will no doubt give recommendations and don't be afraid to pay for quality). Increase in CR and tailor the ignition curve to suit and you'll have a great 1275cc road motor.
Gassing Station | Classic Minis | Top of Page | What's New | My Stuff